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Spatially Resolved Outflows in a Seyfert Galaxy at Z = 2.39

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Spatially Resolved Outflows in a Seyfert Galaxy at Z = 2.39 Spatially Resolved Outflows In a Seyfert Galaxy at z = 2.39 3 3 3 1 1 2 3 2 3 3 1 Travis Fischer , Jane Rigby , Guillaume Mahler , Michael Gladders , Keren Sharon , Michael3 Florian3 , Steve Kraemer4, Matt Bayliss5, Håkon Dahle6, L. Felipe Barrientos7, Eva Wuyts8, Traci L. Johnson3 3 3 1665, NASA's Goddard Space Flight Center, Greenbelt, MD, United States 2University of Michigan 3University of Chicago 4Catholic University of America 5MIT 6University of Oslo 7Pontifical Catholic University of Chile 8Max Planck Institute for Extraterrestrial Physics We present spatially resolved analysis of rest-frame optical and UV imaging and spectroscopy for a lensed galaxy at z = 2.39 that hosts an active galactic nucleus. Proximity to a natural guide star has enabled high signal-to-noise VLT SINFONI + adaptive optics observations of rest-frame optical diagnostic emission lines, which exhibit an underlying broad component with FWHM ∼700 km/s in both the Balmer and forbidden lines. Measured line ratios place the outflow robustly in the region of the ionization diagnostic diagrams associated with AGN. We compare the spatial extent and morphology of the Lyα, UV and dust-corrected Hα emission, and disentangle the effects of star formation and AGN ionization on each tracer. This unique opportunity — combining gravitational lensing, AO guiding, redshift, and AGN activity — allow a complete and magnified view of three main tracers of the physical conditions and structure of the interstellar medium in a star-forming galaxy hosting a weak AGN at cosmic noon. Left: From our strong lensing model, we find the lensing critical line, which separates regions of different image multiplicities, lies directly over the center of the arc of SGAS 0033, such that the north and south ends of the arc are reflections of one another and sample roughly half of the fully imaged galaxy. Right: Source plane reconstruction of the arc shows SGAS 0033 as it would have been seen without a lens. White Figure 2.FigureTop, 2. middle,EmissionTop, and middle, bottom line and rows bottom measurementsFigure display rows 2. centroid displayTop, middle, velocity,centroid from and velocity,FWHM, bottom SINFONI FWHM,and rows integrated display and integratedH- fluxcentroid and maps fluxvelocity, ofK-band mapsH↵ emission-line FWHM, of H↵ IFUemission-line and profiles, integrated profiles, flux maps of H↵ emission-line profiles, respectively,respectively, in the image in the plane. image Left plane. and Leftrightrespectively, and columns right inrepresent columns the image represent the plane. narrow- the Left and narrow- and broad-component right and columns broad-component represent fits of the the fits H↵ narrow-ofemission-line the H and↵ emission-line broad-component profiles, profiles,contours fits of the H↵ emission-linerepresent profiles, rest-frame optical continuum emission. respectively.Figure 2.respectively.FigureTop, Black 2. middle, contoursTop, Black and middle, contoursrepresent bottom and represent integrated, rows bottomrespectively. display integrated, rows continuum-subtracted centroid display Black continuum-subtractedvelocity,centroid contoursvelocity,FWHM, Hrepresent↵ flux images. FWHM,Hand integrated,↵ flux integrated Continuum images. and continuum-subtracted integrated flux Continuum centroid maps flux of is centroid mapsH depicted↵ emission-line H of↵ isflux H bydepicted↵ a images.emission-line cross. profiles, by Continuum a cross. profiles, centroid is depicted by a cross. respectively,respectively, in theobservations. image in the plane. image Left plane. and LeftrightFirst, and columns right second, represent columns represent the narrow-and the and narrow-third broad-component androws broad-component fitsdisplay of the fits H↵ ofemission-linecentroid the H↵ emission-line profiles, profiles,We measuring a radial extent of the outflowing gas in the respectively.Figure 2.respectively.FigureTop, Black 2. middle,velocity, contoursTop, Black and middle, contoursrepresent bottom FWHM, and represent integrated, rows bottom display integrated,rows continuum-subtractedand centroid display integrated continuum-subtracted velocity,centroid Hvelocity,FWHM,↵ fluxflux images. HFWHM, and↵ fluxmaps integrated Continuum images. and integrated fluxof Continuum centroid mapsHα flux of is centroidandmapsH depicted↵ emission-line of is[O Hbydepicted↵ aemission-lineIII] cross. profiles, by a cross. profiles, respectively,respectively, in the image in the plane. image Left plane. and Leftright and columns right represent columns represent the narrow- the and narrow- broad-component and broad-component fits of the fits H↵ ofemission-line the H↵ emission-line profiles, profiles,source plane of r ~100 pc. respectively.respectively. Black contours Black contoursrepresent represent integrated, integrated, continuum-subtracted continuum-subtracted H↵ flux images. H↵ flux Continuum images. Continuum centroid is centroid depicted is bydepicted a cross. by a cross. Figure 2.FigureTop, 2. middle,λ5007.Top, and middle, bottomFourth and rows bottom row display rows displays centroid display velocity,centroid integrated velocity,FWHM, FWHM,and flux integrated and maps integrated flux maps of flux of[N mapsH ↵II]emission-line ofλ H6584↵ emission-line profiles, profiles, -1 N respectively,respectively, in the image in the plane. image Left plane. and Leftright and columns right represent columns represent the narrow- the and narrow- broad-component and broad-component fits of the fits H↵ ofemission-line the H↵ emission-line profiles, profiles,Using this extent, an outflow velocity of 725 km s , and a respectively.respectively. Black contours Black contoursrepresent represent integrated, integrated, continuum-subtracted continuum-subtracted H↵ flux images. H↵ flux Continuum images. Continuum centroid is centroid depicted is bydepicted a cross. by a cross. and Hβ. Black contours represent continuum-subtracted Hα flux 4 images. K-band continuum centroid is depicted by a cross. measured NLR gas mass of 7.4 x 10 M☉, we calculate a mass E outflow rate of Ṁ = 0.55 M☉ yr-1 . F555W F814W Star formation rate (SFR) F105W Hα luminosity measured from the non-AGN ionized gas is converted to a SFR using the Kennicutt (1998) relation and adjusted to the initial mass function from Charbrier (2003). Bottom circle: HST WFC3 F555W/F814W/F105W composite Measuring the source plane Hα luminosities north and south image of the lensed Sloan Giant Arcs Survey (SGAS) galaxy, of the lensing critical line , we find SFRs of 22.8 M☉ yr-1 and SGAS2-0033. SINFONI observations of the target lensed arc -1 are shown approximately by the green box. The bright source 70.7 M☉ yr , respectively. Measuring the individual, extended to the southeast is a star, which was used as the natural guide Hα emission knots offset from the continuum peak, we star for SINFONI adaptive optics. The bright source to the measure a SFR of 2 - 5 M☉ yr-1. southwest is a star, which was used as the natural guide star for SINFONI adaptive optics. Above left: BPT diagram of individual spaniel measurements using the high-redshift classification from Kewley+ (2013). Grey We have analyzed spatially-resolved, rest-frame UV / optical imaging and spectroscopy of a Seyfert AGN at Lyα vs Hα Flux points are single component fits, red points are two-component We find that the Lyα-emitting gas is Hα + [N II] fits. Above right: Separating the two-component fits z∼2 for the first time. Our major findings are as follows: most prominent between, not into narrow (green) and broad (blue) components shows that the 1) Observed AGN-ionized outflows have a maximum cospatial with, the brightest knots of Lyα broad component is AGN ionized. Larger points represent extent of ~100 pc. We calculate a mass outflow rate over Hα that reside over the AGN and likely spectrum from 0.5” x 0.5” binned region over the location of the this distances of Ṁ = 0.55 M⊙ yr−1. The corresponding star-forming regions. This discrepancy broad component gas. between the morphology of Lyα and Below: Gaussian fits to the 0.5” x 0.5” binned spectrum and ratio of outflow power to bolometric luminosity is Hα is similar to what has been resultant fluxes in both the observed image plane and the exceedingly low, log(Ė/Lbol) = -3.76, suggesting that the reported in local starburst galaxies reconstructed source plane. AGN provides little impact on the host galaxy. (Ostlin et al. 2009; Hayes et al. 2013) 2) SGAS 0033 is also exhibits a SFR on the order of 10s Lyα vs Hα Velocity Profile of solar masses per year, which greatly exceeds the We also compare the spectral Lyα AGN mass outflow rate. As such, the current state of the signatures of Lyα and Hα, with Lyα Hα + [N II] AGN in SGAS 0033 would be unlikely to quench star- emission obtained from longslit MagE formation within the galaxy. observations as detailed in Rigby+ 2018. The observed velocity structure 3) AGN outflows have little effect on Lyα structure of Lyα in comparison to Balmer compared to similar galaxies not hosting AGN. emission is typical in studies of green 4) Faint emission-line signatures of AGN combined with pea galaxies (Yang et al. 2017; strong star formation makes detecting AGN at z∼2 Orlitova et al. 2018). extremely difficult without gravitational lensing. .
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